In a new article in the journal Clinical Infectious Diseases, the Center for Disease Control says it closely studied one norovirus outbreak on a cruise ship in 2009, and found that nearly half of the people infected didn’t report it to the infirmary, and thus were not counted in the official tally.
The CDC says 40% of those who became ill on this voyage never reported it to the ship, and that the percentage of sick passengers was 15.4% – much higher than earlier reported.
Specific details on which ship they investigated are on tight wraps, but USA Today’s Cruise log suggests the guest count, length of voyage, and the historical reports point to the Celebrity Mercury.
The study also found this cruise wasn’t alone – that all other cruise lines used similar methods of reporting illness on board.
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